Opnunartíminn stendur hér.

Opnunartíminn is a compound noun:

• opnunar- = of opening
• tími = time
• -nn = the (the suffixed definite article)

So opnunartíminn literally means something like the opening time, but in natural English it is usually understood as the opening hours or the business hours, depending on context.

Icelandic uses compound words very freely, much more than English does.

In Icelandic, the definite article is very often added to the end of the noun instead of appearing as a separate word.

So:

• opnunartími = opening time / opening hours
• opnunartíminn = the opening time / the opening hours

This is completely normal in Icelandic. English learners often expect a separate word like the, but Icelandic usually builds it into the noun.

The ending -inn is the masculine singular definite ending in the nominative for many nouns like tími.

Here the base noun is:

• tími = time

With the definite article:

• tíminn = the time

And inside the compound:

• opnunartíminn = the opening time / the opening hours

The exact form of the article changes depending on gender, number, and case, so you will not always see -inn.

Yes, stendur literally means stands. It is the 3rd person singular present form of standa.

But in this sentence, Icelandic uses standa in a broader sense than English does. It can mean:

• is written
• is stated
• is listed
• appears

So Opnunartíminn stendur hér is not saying the opening hours are physically standing there. It means they are written here or listed here.

This is a very natural Icelandic way of expressing that something appears in writing.

Because Icelandic often uses standa where English would prefer expressions like:

• is written
• is listed
• appears
• says

This is one of those places where a literal word-for-word translation sounds odd in English, but the Icelandic phrasing is completely natural.

So learners should think of stendur hér as an idiomatic expression meaning something like is here in writing.

Hér means here.

It tells you the location where the information appears. So:

• stendur hér = is written here / appears here

It usually refers to the place you are looking at: a sign, a notice, a webpage, a poster, and so on.

This is a normal Icelandic sentence order:

• subject: Opnunartíminn
• verb: stendur
• adverb: hér

So literally:

• The opening hours
  • stand/are written
    • here

That is a very straightforward declarative pattern in Icelandic.

You could move hér for emphasis in some contexts, but the given order is neutral and natural.

Grammatically, opnunartíminn is singular.

That can feel strange to English speakers, because English often uses plural expressions like opening hours. Icelandic may use a singular form where English prefers plural wording.

Depending on context, a natural English translation could be:

• The opening time is shown here
• The opening hours are listed here

So the Icelandic grammar and the most natural English translation do not always match one-to-one.

It is in the nominative case, because it is the subject of the sentence.

The subject is the thing that stands / is written here, so nominative is exactly what you would expect.

For learners, the important point is:

• dictionary form: opnunartími
• nominative definite singular: opnunartíminn

A rough learner-friendly guide:

• opnunartíminn ≈ OP-nu-nar-TEE-min
• stendur ≈ STEN-dur
• hér ≈ hyair or hyehr

A few useful notes:

• í is like ee
• e in stendur is more like eh
• hér has an accented vowel, so it is longer than her
• the rolled or tapped r is important in careful Icelandic pronunciation

This is only an approximation, but it helps get you started.

Yes, very naturally.

It sounds like something you might see when someone is directing you to the place where the business hours are displayed. For example:

• on a sign
• on a poster
• on a webpage
• in a form or notice

It has the sense of The opening hours are shown here or The opening time is listed here.

It is a complete and natural Icelandic sentence.

That said, in real life, Icelandic speakers might also choose more specific or more idiomatic alternatives depending on context, such as expressions meaning:

• The opening hours are listed here
• You can see the opening hours here
• Here are the opening hours

But Opnunartíminn stendur hér is grammatically normal and understandable, especially in a written or informational context.